Universal crane sling



Jan. 21,v 1958 c. J.' KooNs ETAL 2,8205@ UNIVERSAL CRANE SLING Filed April 19. 1956 4l sheets-sheet 1 Y @Um Jam., 21, 1958 c. J. KooNs ETAL 2,320,561

UNIVERSAL CRANE SLING Filed April 19, 1956 4 Sheets-Sheet 2 Jan. 21, 1958 c. J. KooNs ETAL 2,320,651

UNIVERSAL CRANE SLING Filed April 19, 1956 4 Sheets-Sheet 3 Jan. 2i, E958 c. J. KooNs ETAL 2,820,66l

UNIVERSAL 'CRANE SLING Filed April 19, 1956 4 Sheets-Sheet 4.

INVENTORS eff/7m 0. eclcow ilnited States Patent' C UNIVERSAL CRANE SLlNG Clarence J. Koons, Columbia, Pa., and Gerald D. Archdeacon, Fairborn, Ohio, assignors to the United States of America as represented by the Secretary of the Arr Force Application April 19, 1956, Serial No. 579,414

5 Claims. (Cl. 294-78) (Granted under Title 35, U. S. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the United States Government for governmental purposes without payment to us of any royalty thereon.

The subject invention relates to a crane sling arrangement capable of lifting and displacing loads of varied weight and variable Weight distribution. More particularly, subject invention relates to a heavy duty sling which may be adjusted for balanced lifting of loads having different centers of gravity, yet may be securely locked in position for each lifting operation, and easily detached and adjusted for each succeeding lift operation.

The present invention is designed to replace the many different types of slings which were formerly necessary where required to handle and displace load members of different weights and weight distribution. An example of the problem involved presents itself in the cargo loading of aircraft where as many as 35 different types of aircraft must be hoisted and displaced from the dock to the cargo ship, each type of a diiferent weight and each having a different center of gravity thereby requiring a different sling configuration to maintain each aircraft in balance. In the past, the cable type sling has been utilized due to its high strength per unit size; however, it has been found necessary to permanently attach the cable members to the main lift ring, thus requiring availability of a considerable number of slings to balance each different type of load.

A chain type sling, although adjustable, has not been utilized for a number of reasons: In the lifting of heavy aircraft, an extremely bulky, heavy duty chain would be required and consequently, very difficult to manage and adjust; furthermore, it has been dangerous to provide chains that would be adjustable upon the main lifting ring because of their tendency to slip out either when not well secured during the lift operation, or when slack is introduced in the chain after the load is taken off; also, as a result of the comparative low strength per unit weight of chain, a high safety factor is sacrificed in order to permit manageability, thus either presenting considerable danger to those working nearby or requiring constant replacement. An additional deterrent to the use of a universal type sling has been the diversity of attachment fittings provided on the aircraft, thus preventing correlation between the sling attachment and the aircraft attachment.

Slings of the cablev type have thus been primarily resorted to, being safer and easier to handle and possessing good lift strength per unit weight, although providing little or no means of adjustment.4 It is thus a primary object of the present invention to provide a sling which can be made adjustable to conform-for lifting to a variety of loads of diierent centers of gravity, is securely adjustable for each load, and is provided with a universal fastening arrangement for attachment to each load.

It is a further object to provide a heavy duty sling,

ice

light weight in relation to the Weight to be lifted, yet having a high safety factor.

It is a further object to provide a universal sling which due to its light weight and adjustability may be carried with loading apparatus to perform varied handling operations.

It is another object to provide a universal sling arrangement having detachable load fasteners for attachment with fittings permanently provided on the load.

A still further object is to provide a universal sling arrangement which may be securely attached for each lifting operation, further secured against release when unloaded, yet is easily detachable from the load and readily adjustable for each succeeding lifting operation.

With the above-mentioned and other objects in view, the invention includes a gather link having a circular ring for suspension from a standard crane hook, a plurality of slots extending downwardly from the ring, and an annular retainer plate mounted upon the inner periphery of the ring. A plurality of pendent, light weight cables is each suspended from a particular slot by means of a chain provided at one end of each cable for insertion in the slots. Each chain can then be adjusted within the slot in relation to the weight distribution of aircraft or load to be displaced, and inclosed against release by the retainer plate. To make the sling adaptable to the various aircraft types and Various fittings provided on each aircraft, a U-shaped shackle member is provided in swiveled connection at its free ends to the flange por` tion of the attachment ttings of they aircraft. A socket assembly is provided at the lower end of the cable-chain having an insert portion for placement of the closed end of the shackle, a latch arrangement being provided on the socket to lock the shackle against release. The invention further includes the novel parts and combination and arrangement of parts as hereinafter particularly described and claimed.

Figure 1 is a perspective View showing the Vuniversal sling in attached position on the fuselage of an aircraft; Figure 2 is a detailed plan View of the gather link used for adjustable attachment of the cable-chains;

Figure 3 is a side plan view of Figure 2 taken along the lines 3 3 of Fig. 2;

Figure 4 is a detailed sectional view of the socket and shackle assemblies; 4

Figure 5 is a sectional plan view of the socket assembly shown in Fig. 4 showing the bar in unlatched and latched positions;

Figure 6 shows an elevation of a vform of attachment of the sling to an aircraft utilizing a spreader bar;

Figure 7 is a view at right angles to that shown in Fig. 6.

Referring more particularly to the drawings, there is shown in Fig. l the universal sling arrangement 1 having a main gather link or lifting ring 2 suspended from a standard crane hook 3 which is attached to a crane or hoist mechanism (not shown). Figs. 2 and 3 illustrate in more detailed form the gather link 2 having an inner circular ring 4 for attachment to the hook 3. Extending outwardly and downwardly from the periphery of the ring 4 are four longitudinal slots 5, the edges of each slot being rounded or beveled and taperinginwardly from the surface of the link 2 to permit safe and rapid insertion of the chains. Mounted on the inner periphery of the ring 4 is an annular, channel-shaped retainer plate 7 which is arched to extend over the greater portion of the inner periphery of the ring with its ends spaced apart at least the width of one of the chain slots. The plate 7 is assembled on the ring for rotative slidable move` ment thereon by welding the plates 7a and 7b into position on the-ring to the plate 7c. In this way, the plate- Y Y cornerby: means'y ofy a pin 23? fixed acro'ssbthe: slot;-

bar22.. iszfur-therf provided.:with alstopl or-"catch' .24toi1i'mitf m'ovement/ of: the. bar- 22, the lowerA edge of; theslotZl-l 3 is permanently self-locked on the gather link 2, yet may be rotated upon the ring 4 to open and close the slots 5.

Fig. 1 further shows the pendent cable-chain members Seach-provided with-1aV chain length lfattachedlby; means; of a coupling 11 to the upper end `off thecable 9 The coupling means 12y provided for the, interconnection of each cable-chain and anaircraft-6 tobe liftedy broadly' compriseansocket assembly-15 and shackle members 14,

the lower end of each cable-chain member 8 being se-Y curely attached' by-means of' awswaging operation-within agbore: 16 provided withintheiupper cylindrical ortubulark portion 15.

As shown inrFigs;` 4f and 5; each. tubulan portioll-flS" is ared outwardly; at itsy upper'endl 16a toY prevent sharp" bendingiofeach..r cable v9.'I Y 'Ihesocket 13 Yfurther 'includes aloiwergt enlarged cylindricaluportion orfthimble 1T in tegral with the upper portion .15. and vjoined therewith? by, means o anzoutwardly-taueredishoulder-'portion18.'- .The lowerportion 17 isprovidedzwith.: anoblongsocket' orpocket` 19 extending axially. -ther lengthvr ofther portions; 1-7

and converging: at its inner extremity into the` bore'16 Positioned onf diametricallyl opposedfsides'. ofi the lower.V portion 17`are slotted sectionst-20and-21 passing-laterally into.; theflower portions' to communicate. with opposite sides; of; the" pockety 19. Aulatch or loclcirigtbarl 221i's` pivotally. mounted within'theislot 20.5 at itsflowe'r inside Theactingfasfalstop for tbe'b'ar- 22 asiishownlintFig.'

havinga U-shaped f tongue portion.` 2'6 and oval-"shaned` freetend portions 28.. The shackle14ispreferablycoi+ nected to'suitable attachment tittin'gstlhavingl a-'llang'ei 312 ori otherV suitablenneans for? plac'ement between? the? free end portion'siZS. Both ltl'lelfree-endlpoitions1 A2S andi' the ilange 311arel provided with--bores'27la'ndlthe bore' 32= respectively. for. insertion of the pinshackle 29; thereby permitting-pivotal movement of the shackl'ev1'4l onfthe ange. 4

Figs; 6.and 7 illustrate the use ofthe universal slingl in which a spacer or spreader bar maybe-used to spread the cable-chains 8 apart in lorder to provideclearancebe tween the load'to be'liftedand the sling.

In operation, eachof the links Vtof the chain'9 is marked or indexed to conform with the particular arcraftft'be loaded;` Inl this way, when anaircraft' orlo'ad isto' be lifted, each of the chains 9 will be inserted into the-slots S atth'e link-"marking relatingfto lthefaircraft'in-oi'der'l to maintainth'ez-center of'gravityA of the aircraftdir'ectly'beneath the gather link 2 thereby balancing' thef aircraftlv forloading.' The retainer plate 7 is, of courser`otrated to an upwardly disposedpostiononthe rin`g3totpermit insertionor adjustments of'the chains@ 9: Sincethe'fjretainer plate 7 encloses the greaterV portion offthe 'ringperiphery, it is necessary to rotate the retainer plate'affsucrcessive number of times toopenallof the slots Sfortthe chain insertion.` After insertion," the retainer plate isf' rotated downwardly across the mouth ofthe openings 5 to'- enclosethe-chains 9 Withinjthe slots The-.shackle=memberf 14r may be easily and'i rapidly inserted, andflocked Within'eac-h socket assembly-'12h51v lowering the pocket 19 over the outer, yclosed-endet? they tonguet26. The closed end of the tongue,=asrit is-forced' upwardly into the pocket, Will forcethe .latchbar-ZZ out of the socket and to a substantially uprightlpositionvinf the slot 20, the bar 22 leaning against the closed end ofthe tongue, as shown dotted in Fig. 4. After the shackle passes the'end ofthe bar Z2,` the bar willl fall backv or may be manually pivoted, within the tongueand into the slotv Usually,` two forward attachments' and `two"rearvv'a'rd attachments 'are provided on'A each aircraft. If necessary,

suitable spacingv means; such",w asv the'l spreader bar" QS? shown in' fEigs: '6- and 7 may be combine'dlvvitlf'thesling" "a-,fsaneai arrangement. Of course, if preferable or necessary, `a diiferent number of` slots, or differenty number of cablechains may be provided without deviating from theprinciples and advantages ofthe invention.y An added feature is the utilization throughout of a cable member 9 which will tend to tighten rather'than loosen each attach. ment fitting Sllfdur'ingthe' liftingfoperatio'n This is accomplishedmerely by providing afcablewhich will tend to unwrap when? a loadY is" appli'ed in'N the diretionof' tightening ofthe.relatediitting;l For instance-,Twherefthe Y,

attachment littings 30 are v provided with right-hand threads,A as. shown in Fig: 5 the cable` strands should have a leftlha'nd or clockwisely; asishowniimFig. l so that the tendency will beto unwrapina counterclockwise direction thereby acting to tighten the fitting upon the aircraft:v

Upon lifting the aircraft off the ground, each shackle 14 v will vb'elrestrain'ed against release 'byv `theIinterpositi'oned bal-S522.l During,the.liftingoperationtheswiveled shacklesl 14 willi permit shifting of.` the. aircraft withoutl imposing'.

undue binding stress on the cables. The chains willVof course', besecurednagainst any-'possibilityof release from thefslots 5sinceV thehook 3f will.' prevent `any upward' shifting-f onrotation o'f the-plate 7'. Y

Upon conclusion" of? the? lifting'. operationV the. chainsl WillLremaini inf/pusitionlnntil manually' released by-r'otat-r chain,:. ifi? neees'sary5--fmayl then be adjusted for the llifting of anothera'ir'c'rafti` l To' accommodate ftheh'eavi'er loads'required to be' lifted,

paratively; rheavy lwith2're'.spetftol the l cable; however,` the chainL-lengths providedfwill beljust sufcientl to providetheineoes'sary different.-slinifcon'rlgurations.i In this way, the adjustabili-tyof the `chan1's`,-and` liftingfstrengthof-the cable" are 'utilized'lt advantage.l

For purposesffr ofe pliliation particular emb'odid mentsl ofv the invention-have been shown and described' aecordingl to the.: bestf-Vv preseritlV understanding thereof. However," it? Willi'be" apparent that many? changes and#` modifications I inthe" arrangement afn'dV construction ofVY theparts'i thereof may bei' resorted to Without departing?? l. A universal sling ccmprising a lift ring-for suspen-v sion" from a-@cr'aneg said ringhavin'g af central-opening 2'. A. light'weight,universal slingV for the" lifting and displacement'ofaf'plurality of? loadmembers bya crane wherein each load varies` inweight distribution necessitatfA ing-a Varied-sling configuration; said slingcomprising: aL

central support having acircular openingY extending transversely therethrough, a plurality of slots extending out-V wardly from the periphery. of said opening, and an annular retainer plate rotatably mounted upon the periphery of said" opening.' toV permit" o'peirlii'ng an'V closing ofsaid/ slots; a 'pluralityofpendent lightweight cables 'each provided'w'ithalength of chainf'atione en`d,"the"link'sI of'reach" of said Ichains selectively inserted' infsaidslots rin rela'-` tion'r to the-weight'distributienet*the'tloadto;be'displaced.

and` retained' 'in sailcslts against releaseby said Vretainer platejan'd "securingmeans1 adapted'Y to attach said 'cablesandadfli?? a 3? A Vliftringfbrr'adustableattachmentofc'a plurality of chains thereto, said lifting ring having a transverse opening to receive a crane hook or the like, a plurality of chain slots spaced along the lower periphery of said opening in radial fashion, the upper end of each slot communicating with said transverse opening to receive a chain link in close ltting relation therein, and a channel shaped annular retainer plate rotatably mounted on the periphery of said opening for slidable disposition over said slots to retain the links Within said slots, and slidable away from said slots to release the links therefrom.

4. A lightweight, universal sling for the hoisting of a load member, said sling comprising: a lifting ring having a transverse opening for placement of the lifting ring on a crane hook or the like, a plurality of chain slots notched outwardly from the periphery of said opening, and an annular, retainer plate disposed on the periphery of said opening, said retainer plate being of a length sufdcient to simultaneously cover said slots and movable about the periphery of said opening to uncover each of said slots; a plurality of pendent, lightweight cables each provided with a length of chain coupled to one end thereof for insertion into a respective chain slot, said chains retained in said slots against release by said retainer plate; and securing means adapted to attach said cables to the load member.

5. A universal sling for lifting and displacing load members of varied weight distributions, said sling comprisng: a support member having a central opening to accommodate a crane hook or the like and a plurality of slots extending outwardly from the side of said opening, a plurality of pendent members each including means at one end proportioned for insertion into a respective slot and proportioned for engagement with the sides of each respective slot to connect said pendent members to said support member and means at the opposite end of each pendent member to secure said pendent members to the load to be lifted, said support member having a retainer member for disposition on the side of said opening to inclose said means at said one end of said pendent members to prevent accidental separation of said means from said slots.

References Cited in the file of this patent UNITED STATES PATENTS 1,326,969 Rounds Ian. 6, 1920 2,009,938 Manbeck July 30, 1935 2,200,044 Shannon May 7, 1940 2,343,045 Butler Feb. 29, 1944 2,492,172 Morris Dec. 27, 1949 2,721,757 Anderson Oct. 25, 1955 FOREIGN PATENTS 108,409 Sweden Sept. 7. 1943 

